Construction of ships



.l. M. THOMPSON. CDNSTRUCTION 0F SHIPS. APPLICATION FILED JULY 5.1919.

Patented Sept. 14,1920.

JAMES M. THOMPSON, OF BUFFALO, NEW YORK.

CONSTRUCTION OF SHIPS Specification of Letters Patent. Patented Sept. 14, 1920.

Application filed July 3, 1919. SerialNo. 308,563.

To all whom it may concern:

Be it known that I, JAMns M. THOMPSON, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented new and useful Improvements in the Construction of Ships, of which the following is a specification.

This invention relates to the construction of freight boats, battle ships and other craft of various kinds.

Its object is to improve the vessel with a view of stiffening its hull and increasing the buoyancy of the vessel, as well as diminish.

ing the so-called skinfriction and dislodging barnacles.

In the accompanying drawings: Figure 1 is a side elevation of a vessel embodying the invention. Fig. 2 is a cross section amidships. Fig. 3 is a fragmentary horizontal section on line 3-3, Fig. 2. Fig. 4 is a fragmentary bottom plan view of the hull.

Similar characters of reference indicate corresponding parts throughout the several views.

The body or main portion of the hull may be of any desired or approved construction, that illustrated in the drawings comprising theusual frame-members 11, 12 and 13 of structural steel and lapped sheathing plates 14. These plates may extend over the entire bottom as well as the sides of the frame, as customary, but in the preferred construction shown, they extend down the sides of the hull-frame a suitable distance below the water line, the rest of the sides and bottom of the hull being covered by or consisting of a buoyant shell or envelop which constitutes my improvement.

This shell preferably extends from bow to stern of the vessel and from the-lowermost band of sheathing plates 14 to the keel 15. It is composed of spaced inner and outer walls 16 and 17 connected together at their upper edges by a top plate or ledge 18 and abutting at their lower edges against the sides of the keel, the oints at the upper and lower edges of these walls being air tight to form a hollow buoyant covering for the lower or submerged part of the hull. The shell may be constructed of lapped steel plates like the sheathing plates 14:, but of somewhat smaller gage, inasmuch as the shell is double. Its inner wall practically forms a continuation of the sheathing plates and it is therefore unnecessary to extend the latter to the keel as in ordinary ship construction.

In the preferred form of the shell, its outer wall is grooved or corrugated in a substantially vertical or transverse direction from end to end and from top to bottom thereof, as shown, the bases of the corrugations bearing against the inner wall 16 to form a series of tight air cells 0 compartments 19. I

This cellular shell increases the buoyancy of. the vessel and enables it to carry a correspondingly greater amount of freight, while its corrugated construction materially stiffens or reinforces the hull.

The rough undulating surface presented by these corrugations agitates and breaks up the water coursing along the hull while the vessel is in motion, thus washing off or dislodging any barnacles clinging to it. This agitation also breaks the partial vacuum ordinarily create d along the sides of the ship, reducing the resistance or skinfriction resulting from the vacuum.

The closed top 18 of the buoyant shell is preferably abrupt, as shown. By this construction, a ledge or shoulder is formed around the hull, which, being located some distance below the water line, serves to resist rolling of the vessel.

. While affording these several advantages, the improvement does not materially add to the cost of the vessel.

I claim as my invention:

1. A vessel having its hull provided with external corrugations extending transversely of its bottom and sides.

2. A ship-hull having a shell composed of spacer inner and outer walls, the outer Wall having transverse corrugations whose bases bear against said inner wall.

3. A boat-hull comprising a frame, sheathing plates covering the upper portions of the frame sides, and a hollow, airtight shell applied to the bottom and the lower portions of the frame-sides and comsists rolling of the vessel.

JAMES M. THOMPSON. 

